Cooling panel

ABSTRACT

A panel includes a sheet of heat-shrinkable polymer material and a packet coupled to the sheet. The packet contains a reactant that is activated in response to the sheet shrinking.

FIELD OF THE INVENTION

The present invention relates to articles for cooling temperature-sensitive items, and more particularly to articles that experience an endothermic reaction when heated to a predetermined temperature.

BACKGROUND OF THE INVENTION

Many portable electronic devices can be adversely affected by heat. When electronic devices are stored in high heat environments, such as the interior of an automobile on a hot day, they may suffer significant damage that compromises the functionality of the device as well as any stored data.

SUMMARY OF THE INVENTION

The invention provides, in one aspect, a panel including a sheet of heat-shrinkable polymer material and a packet coupled to the sheet. The packet contains a reactant that is activated in response to the sheet shrinking.

The invention provides, in another aspect, a container including a compartment in which a temperature-sensitive item is receivable and a panel in thermal communication with the compartment. The panel includes a sheet of heat-shrinkable polymer material and a packet coupled to the sheet. The packet contains a reactant that is activated in response to the sheet shrinking The reactant undergoes an endothermic reaction when activated to remove heat from the compartment.

Other features and aspects of the invention will become apparent by consideration of the following detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a cooling panel in accordance with an embodiment of the invention, illustrated in an inactivated state.

FIG. 2 is an enlarged perspective view of a portion of the cooling panel of FIG. 1

FIG. 3 is a perspective view of the cooling panel illustrated in an activated state.

FIG. 4 is an enlarged perspective view of a portion of the cooling panel of FIG. 3.

FIG. 5 is a perspective view of an exemplary container incorporating the cooling panel of FIG. 1.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

DETAILED DESCRIPTION

FIG. 1, illustrates a cooling panel 10 including first and second interconnected sheets 14, 18 of a heat-shrinkable polymer material. The interconnected sheets 14, 18 may define a self-corrugating polymer panel such as those described in U.S. Patent Application Publication Nos. 2014/0087145, 2014/0087146, and 2014/0087147, the entire contents of all of which are incorporated herein by reference.

Before assembling the cooling panel 10, each of the sheets 14, 18 is uniaxially stretched to impart direction or orientation in the polymer chains. The sheets 14, 18 are oriented so that the stretched direction of the first sheet 14 is generally perpendicular to the stretched direction of the second sheet 18. A radio frequency (RF) or other suitable welding process is used to create weld spots 22 that permanently bond the sheets 14, 18 at evenly-spaced intervals.

With reference to FIGS. 1 and 2, the cooling panel 10 also includes reactant packets 26 located between the sheets 14, 18 and interconnected to the sheets 14, 18 by the weld spots 22. The reactant packets 26 contain a first, liquid reactant 30 and a second, powdered reactant 34 enclosed within a frangible capsule 38 that is immersed in the first reactant 30. In the illustrated embodiment, the first reactant 30 is water and the second reactant 34 is ammonium nitrate. As described in greater detail below, when the two reactants 30, 34 mix, they produce an endothermic reaction:

NH₄NO₃₍₈₎+Heat→NH₄ ⁺ _((aq))+NO₃ ⁻ _((aq)).

This reaction cools the panel 10 and its surroundings. In other embodiments, the second reactant 34 can be any other substance suitable for producing an endothermic reaction when mixed with water. For example, the second reactant 34 may include calcium ammonium nitrate or urea. Alternatively, the first reactant 30 may include any other liquid or gel, and the second reactant 34 may include any other substance suitable for producing an endothermic reaction when mixed with the first reactant 30.

With reference to FIGS. 3 and 4, when the cooling panel 10 is heated to a predetermined temperature, the first and second sheets 14, 18 shrink along orthogonal axes, creating undulations 42 in each of the sheets 14, 18 between adjacent weld spots 22. This deformation causes the frangible capsules 38 to rupture and mixes the first and second reactants 30, 34 to trigger the endothermic reaction (FIG. 4).

In operation, the cooling panel 10 begins shrinking from its inactivated state shown in FIGS. 1 and 2 to the activated state shown in FIGS. 3 and 4 when it is exposed to a predetermined temperature (e.g., about 120 degrees Fahrenheit). As the interconnected sheets 14, 18 shrink, the weld spots 22 are displaced relative to each other, causing the capsules 38 to rupture. The reactant 34 (e.g., ammonium nitrate) empties from the capsule 38 and mixes with the reactant 30 (e.g., water), beginning the endothermic reaction. As the reaction progresses, the temperature of the cooling panel 10 decreases substantially to cool the ambient surroundings of the cooling panel 10. In the illustrated embodiment, the temperature of the cooling panel 10 may be reduced by about 85 degrees Fahrenheit.

FIG. 5 illustrates a container 50 having a compartment 54 in which a temperature-sensitive item (e.g., a laptop, music player, hard drive, cellular phone, etc., not shown) is receivable. In the illustrated embodiment, the container 50 is a briefcase; however, the container 50 may be a laptop sleeve, backpack, suitcase, or any other container suitable for storing or transporting a temperature-sensitive item. One or more cooling panels 10 may be inserted into the container 50 such that they are in thermal communication with the compartment 54.

Should the container 50 with the enclosed device be exposed to a high temperature (e.g., in a closed vehicle) that might otherwise damage or cause the device to malfunction, the one or more cooling panels 10 in the container 50 may be activated in the manner described above to thereby cool the compartment 54 and the device. Once activated, the one or more cooling panels 10 can be removed and replaced with new, inactivated cooling panels 10.

Various features of the invention are set forth in the following claims. 

What is claimed is:
 1. A panel comprising: a sheet of heat-shrinkable polymer material; and a packet coupled to the sheet, the packet containing a reactant that is activated in response to the sheet shrinking.
 2. The panel of claim 1, wherein the reactant undergoes an endothermic reaction when activated.
 3. The panel of claim 1, wherein the reactant is a first reactant, and the packet further contains a second reactant that mixes with the first reactant in response to the sheet shrinking.
 4. The panel of claim 3, wherein the first reactant includes a liquid and the second reactant is contained within a frangible capsule immersed within the liquid.
 5. The panel of claim 4, wherein the capsule is ruptured in response to the sheet shrinking.
 6. The panel of claim 4, wherein the first reactant includes water and the second reactant includes ammonium nitrate.
 7. The panel of claim 1, wherein the packet is one of a plurality of packets coupled to the sheet, each of the packets containing the reactant.
 8. The panel of claim 1, wherein the sheet is configured to shrink when exposed to a temperature greater than or equal to about 120 degrees Fahrenheit.
 9. The panel of claim 1, wherein the sheet includes at least two layers of the heat-shrinkable polymer material, and wherein the packet is located between the layers.
 10. The panel of claim 9, wherein the layers are interconnected by a plurality of weld spots located at spaced intervals.
 11. The panel of claim 10, wherein the layers form undulations between adjacent weld spots when the sheet shrinks.
 12. The panel of claim 10, wherein the packet includes opposite first and second ends that are interconnected to the layers by a first and a second of the weld spots, respectively.
 13. A container comprising: a compartment in which a temperature-sensitive item is receivable; and a panel in thermal communication with the compartment, the panel including a sheet of heat-shrinkable polymer material, and a packet coupled to the sheet, the packet containing a reactant that is activated in response to the sheet shrinking, wherein the reactant undergoes an endothermic reaction when activated to remove heat from the compartment.
 14. The container of claim 13, wherein the reactant is a first reactant, and wherein packet further contains a second reactant that mixes with the first reactant in response to the sheet shrinking.
 15. The container of claim 13, wherein the first reactant includes water and the second reactant includes ammonium nitrate contained within a frangible capsule immersed within the water, and wherein the capsule is ruptured to mix the first and second reactants in response to the sheet shrinking.
 16. The container of claim 13, wherein the packet is one of a plurality of packets coupled to the sheet, each of the packets containing the at least one reactant.
 17. The container of claim 13, wherein the sheet is configured to shrink when exposed to a temperature greater than or equal to about 120 degrees Fahrenheit.
 18. The container of claim 13, wherein the sheet includes at least two layers of the heat-shrinkable polymer material, and wherein the packet is located between the layers.
 19. The container of claim 18, wherein the layers are interconnected by a plurality of weld spots located at spaced intervals, and wherein the layers form undulations between adjacent weld spots when the sheet shrinks.
 20. The container of claim 19, wherein the packet includes opposite first and second ends that are interconnected to the layers by a first and a second of the weld spots, respectively. 